Key blank



S. SEGAL KEY BLANK A ril 2, 1929.

Filed Nov. 24, 1925 INVEN TOR.

BY I 7 '7 A TmkNEYs.

Patented Apr, 2,1929.

. UNITED STATES SAMUEL SEGAL, OF NEW YORK, N. Y.

KEY BLANK Application filed November 24, 1925. Serial No. 71,063.

This invention relates to an improved type of key blank.

It is an object to provide an article of this character which may beproduced at less expense than similar articles as heretoforemanufactured and which may be cut more expeditiously to provide acheaper finished key.

Another object of the invention is that of providing a blank in whichthe percentage of faulty cuts will be reduced to a minimum.

A still further object is that of furnishing a blank which may beutilized to advantage in testing the accuracy of a key-cutting machineso that the correctness of the gauge thereof maybe readily proved. i

{An additional object is that of providing an article which willefiiciently perform the purposes for which it is intended. 7

Other objects of the invention will in part. be obvious and will in partappear hereinafter.

With these and further objects in mind the invention comprises anarticle of manufacture possessing the features, properties and, therelation of elements which will be exemplified in the articlehereinafter described and the scope of the application of whieh will beindicated in the claims. i For a fuller understanding of the nature andobjects of the invention reference should be had to the followingdetailed. description taken in conneetionwith the accompanying drawings,in which:

Figure 1 is a side elevation of a key blank embodying the improvedconstruction of the present inventionand shows the same applied to acylinder lock, the latter being indicated in dotted lines;

Fig. 2 is a transverse sectional view of said blank; and

Fig. 3 is a view similar to Fig. 1 but showing a different form oftheinvention from that shown in the preceding figures; l This inventionis particularly directed to blanks for keys to be used in cylinderlocks. In locks of this character the housing is formed with a borewithin which a plug is rotatable. This plug is formed with alongitudinally-extending key slot into which one or more ribs usuallyextend; A; number of openings havetheir inner ends in communication withthis key slot and extend through to the outer face of the plug, and pinsare positioned within these openings. 7 The hous ing is ordinarilyformed with openings corresponding in number to the plug openings.

Pinsare positioned one within each of the housing openings and areusually urged into the bore thereof by springs. Normally, the openlngsof these two elements align, and the tumbler pins of the housing extendinto the openings of the plug and thus prevent a turning thereof.v

Any suitable number of openings and pins are employed, and they areusually spaced equidistant from each other. Ordinarily, the plug pinsvary in length in order to provide What may be termed the permutation ofthe lock, and the key which operates the lock s cut to have bittingswhich vary in length inversely to the pin lengths of the plug. Thus,when the key is disposed within the key slot of the cylinder plug theouter ends of the pins will all lie flush with the outer plug face andmove the housing pins into retracted position so that the plug may beturned within I the housing to operate the lock. Key blanks are ofcourse furnished in varying lengths corresponding to'the length bf thekey cylinder and in order to permit of the forming of bittingscorresponding in number to the number oftumbler pins which are to'beoperated. Different types of blanks are furthermore furnished which havean inherently different arrangement of grooves extending longitudinallyof their bodies and corresponding to the arrangement oflongitudinally-extending ribs forming a part of the key slot of theplug. It has been usual in referring to the cuttingof the longestpracticable hitting-i. e., the projection of the key which has its apexat a maximum distance from the key axisas necessitating a zero cut ofthe blank, and progressively shorter bittings have been referred to bycorresponding numbers or symbols.

WVith the foregoing in mind, the present invention provides a key blankpreferably of the cylinder lock type in which that edge of the blank inwhich the bittings are to be cutinay be provided-With a series ofnotches at points in line with the points at which the tumbler pins willengage the key when the plug is turned. Thus, in the drawings, thenumeral 5 indicates the body of the blank key, and 6 the grooves, whichextend longitudinally thereof; the reference number 7 indicatingthatedge of the key in Which the bittings are to be formed, and'8 thenotches in this edge. These notches, in the present instance, extend toa depth equal to a zero-cut hitting but it will be appreciated that, ifi desirable, they might extend to a less depth. However, according tothe illustrated form of the invention, by having the notchesoi' just azero-cut depth, no cutting on the part of the key-cutting machine willbe necessary to form the apex of a zero-cut hitting wheir the same isecountered. In other words, that part of the cutting of the key blankhas been" accomplished at the time the blank was died out.

Accordingly, when an operator has a key blank which is to be cut toprovide a finished key, it will be obvious that less cutting has to bedone in order to provide such key than has heretofore been necessarywhere a con ventional blank was being utilized. It is furthermoreapparent that due to a blank being furnished which has a roughened upperedge (i. e., notches in such edge) the thumb or fingers of an operatorwill engage the key so that the blank will be rammedv home in thecutting machine, and consequently, the bittings in the key being formedwill correspend in location, with respectto the key body, to thebittings of the guide key. In dieing out blanks of the type embraced inthe present invention more scrap metal will be vailablev incident to theforming of the notches, so that aside from the fact that the dieing-outoperation will be no more expensive than in the case of the conventionalkey blank, the blank of the present invention may i be manufactured morecheaply, and it will also be obvious that if an operator is desirous ofchecking the gauge of the cutting machine this may be readilyaccomplished by simply utilizing two of these blanks and placing one ofthem in the guide-holder, and the other in the blank-holder. Under theseconditions, and with the. cutting machine not operating, the cutter ofthe latter should ride intothe notches of the blank at exactly thosemoments When the guide of the machine enters the notches of acorresponding blank held by the guide clamp. In addition to thisadvantage, an operator when utilizing a blank constructed within theterms of the present invention will always present the hitting edge tothe cutting or milling tool, in that this edge will be plainlyindicated. A

It will be appreciated that in lieu of the gaugema'rks provided by thenotches other au e marks mi ht be furnished as for exgeneric andspecific accomplished, and since certain changes may be madein the abovearticle, and different embodiments of the invention could be made,without departingirom the scope thereof it is intended that all mattercontained in the above description or shown in the accompanying drawingsshall be interpreted as illustrative'and not in a limiting sense. i

It is also to be understood that the followirg claims are intended'tocover allot the 2. As an article of manufacture, a key features of theinvention blank, including a body having an edge in which bittings areto be formed by akeycutting machine and a series of-notches in said edgeandot a depth not in excess of a zerocut. 3. As an article of manufactura'key blank, including a body having an edge in which bittings are to beformed by a keycutting machine and a series of notches in said edge andat points in line with the tumbler pins of alock which said key is tooperate] lfAs an article of manufacture, a key blank, including a bodyhaving an edge in which bittings are to be formed bya keycutting machineand a series of notches in said edge and at'equi-spaced' points in saidedge and in line with the tumbler pins of a lock which said key is tooperate, the depth of said notches being not in excess of a 'zero cut. i

' 5. As an article of manufacture, a key blank, in one e dge of whichbittings of different heights are to be formed by a key cutting machine,such edge of the blank being partially cut L cutting machine.

6. 'As an article of manufacture, a key blank, including a body havingan edge in which the finished bittings are to be formed by akey-cutting'machine, said edge presenting partly formed bitt-ings. i

7 an article of manufacture; a key blank having groove in one of itsside faces extending longitudinallyof its body and preorior toitsapplication to'the senting an edge inwhich bittings are to be formed bya key-cutting machine and a series of notches in saidedge. f i i I 8. Asan article of manufacture, a. key blank having a groove in one of itsside faces extending longitudinally of its body and presenting an edgein which bittings are to be formed by a key-cutting machine and a seriesof notches in said edge and of a depth not. in excess of a zero cut.

9. As an article of manufacture, a key blank to be rotated and includinga body having an edge in which a permutation of bittings of variousheights are to be cut by a ke cutting machine, and a series of gauge mars associated with such edge.

10. As an article of manufacture, a key blank for use in the rotatableplug of a cylinder lock and including a body having an edge in which apermutation of bittings of various heights are to be cut by akey-cutting machine, and a series of gauge marks for such machine andassociated with such edge and at equi-spaced points in said edge in linewith the tumbler pins of a lock which said key is to operate.

11. As an article of manufacture, a key blank to be rotated to operate alock and in eluding a body having an edge in which a permutation ofbittings of various heights are to be cut a key-cutting machine, suchedge being substantially continuous and of a height substantially equalto the highest bitting which is to be cut in said edge.

12. As an article of manufacture, a keyblank for use in connection withthe rotatable plug of a cylinder lock and including a body having anedge in which bittings are to be formed by a key-cutting machine,portions of such edge being of a height substantially equal to thehighest bitting which is to be cut in such edge.

In testimony whereof I afiix my signature.

SAMUEL SEGAL.

